It has become common for users of mobile devices to send messages over wireless networks to other mobile devices. Such messages include text messages sent as Short Message Service (SMS) messages. Some types of messages, such as Multimedia Messaging Service (MMS) messages, also allow other types of media to be sent instead of or in addition to text, such as images, audio, and video.
Messaging standards have advanced to provide additional features beyond simply sending messages. For example, GSMA's Rich Communication Services (RCS) standard can allow devices to be informed when sent messages have been received, as well as when users are drafting reply messages on other devices. RCS also supports other advanced features, including group chat, file transfers, and content sharing.